If you're limited to factory ammo from your local Dick's, Cabela's, Bass Pro Shop, or Gander Mountain then I suppose that the .450 would be a good cartridge. However, if you handload or don't mind ordering your ammo, the .450 can't really do anything that the .45-70 can with more common and less expensive brass.
Smith, and Wesson, and Me. -H. Callahan
Well waddaya know, one buwwet weft! -E. Fudd
All bad precedents begin as justifiable measures. -J. Caesar